Hydroxyapatite Chitosan Gradient Pore Scaffold Activates Oxidative Phosphorylation Pathway to Induce Bone Formation

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Porous gradient scaffolds composed of hydroxyapatite microtubules (HAMT) and chitosan (CHS) were developed.
• These scaffolds aim to investigate their potential in inducing osteogenesis.

Purpose of the Study:

• To prepare and characterize HAMT-CHS scaffolds with controlled pore structures.
• To evaluate the in vitro and in vivo performance of these scaffolds for bone regeneration.

Main Methods:

• Scaffold fabrication involved controlling wax ball arrangement to create gradient pore structures.
• Systematic in vitro and in vivo evaluations assessed biocompatibility, biological activity, and regulatory mechanisms.
• Micro-computed tomography (CT) was used for in vivo analysis of new bone formation.

Main Results:

• Scaffolds exhibited porosity >80% with interconnected gradient pores, particularly in 50% and 70% HAMT-CHS compositions.
• The 70% HAMT-CHS scaffold demonstrated superior anti-compressive strength.
• In vitro tests confirmed good biocompatibility, enhanced osteogenic gene/protein expression, and activation of oxidative phosphorylation.
• In vivo studies showed significant new bone formation in rat skull defects within 8 weeks.

Conclusions:

• HAMT-CHS scaffolds effectively accelerate osteogenesis in bone defects.
• The mechanism involves potential activation of the oxidative phosphorylation pathway.
• These findings underscore the therapeutic potential of HAMT-CHS scaffolds for bone regeneration applications.